1. Field of the Invention
The present invention relates to a dispensable hypodermic syringe for dispensing medicament from or drawing blood into a cartridge having a needle attached to one end thereof and a finger grasp including an actuating device attached to the other end thereof.
2. Description of the Prior Art
One form of hypodermic syringe typically includes a generally cylindrical barrel including a piston rod therein. The rod includes a handle at one end to facilitate reciprocating movement of the rod within the cylindrical barrel. In such a hypodermic syringe a cartridge is provided having a needle attached thereto, the cartridge being inserted into the cylindrical barrel to work in combination with the piston rod to dispense or receive liquid such as medicament or blood, respectively, in response to movement of the piston rod within the barrel. In this form of syringe the piston rod is connected to a plunger in the inserted cartridge, axial movement of the piston rod causing corresponding axial movement of the plunger to dispense the medicament from the cartridge or receive blood within the cartridge depending upon whether such movement is a dispensing or aspirating movement. Such hypodermic needles are well known in the art and examples include embodiments described in U.S. Pat. Nos. 2,524,367 to Smith and 4,744,790 to Jankowski et al.
One problem that occurs during use of such a hypodermic syringe is that of accidental exposure of the user of the syringe to whatever contaminants might be present upon or within the needle or cartridge after use thereof. For example, in those instances where the needle and cartridge are to be removed from the barrel and disposed of, it has been necessary for the user to grasp the needle to the needle and cartridge assembly from the barrel. Such grasping can expose the attendant to any contaminant which is on the exterior surface of the needle and cartridge, particularly if the attendant is not wearing a glove. In addition, not infrequentlY the attendant might be accidentally punctured by the needle while attempting to remove the needle and cartridge and corresponding contamination of the user will obviously result. Somewhat related to these problems is the not unlikely possibility that the attendant might drop the needle and cartridge assembly while removing the assembly from the barrel structure resulting in undesirable contamination of the area exposed to the needle and cartridge. A similar problem is the possibility that the needle and cartridge assembly might prematurely fall out of the barrel like holder during the disposal operation. In any event, accidental contamination of a medical attendant or anyone else can present a serious health problem especially if the contaminant is an infectious disease such as hepatitis, AIDS and the like.
In order to prevent undesirable contamination, it is highly desirable to provide a disposable hypodermic syringe. Similarly, it is also desirable to provide a disposable hypodermic syringe which can be readily assembled for use. A further object is to provide a disposable hypodermic syringe wherein all of the component parts can readily assembled and held rigidly together. Another object is to provide such a disposable hypodermic syringe which can be quickly assembled.